2012 cotton beltwide curry poster2
Transcript of 2012 cotton beltwide curry poster2
A cotton field in Appling County planted to a heavy cover-crop of rye was fumigated
with Telone II, 4 gal/A, weeks prior to planting. A good stand was established
despite the heavy residue. Fumigation process was difficult because cover crop had
not been “killed”.
Management of Southern Root-Knot Nematode
in Appling County, Georgia
Special Thanks to: Jeff
Deen (right), Greg Black,
Lamar Turner, Satilla Cotton
Gin, Dow AgroSciences, and
Phytogen Cotton Seed.
RESULTS and DISCUSSION (continued)
4. Use of PHY 367 did not result in a decrease of late-season root
galling nor did it result in decline of late-season nematode
populations as compared to PHY 375. PHY 367 out-yielded PHY
375 by 191 lb/A lint.
5. Use of Telone II resulted in numeric increase in yield and gin turn-
out and numeric decline in late-season root damage. Telone II was
the most important production practice in this study to be of benefit
to the grower.
6. Efficacy of AVICTA Complete Cotton to manage nematodes in this
study was tied to the area of the field where evaluated. Where
nematode populations were moderate, the treatment appeared
appropriate.
INTRODUCTION
Appling County lies in the Coastal Plain of southeastern
Georgia. Cotton is an important crop for growers in this county
and management of plant-parasitic nematodes is especially
important as soils in the county are typically very sandy.
Meloidogyne incognita, the southern root-knot nematode, is the
most important nematode affecting cotton in this region.
Growers have historically used aldicarb, Temik 15G, to manage
both thrips and nematodes; however the loss of Temik 15G
early in 2011 necessitated additional field trials to determine
refined opportunities for control of nematodes in Appling County.
The objective of this study was to compare the performance of a
cotton variety with known partial-resistance to the root-knot
nematode (PHY 367B2RF) treated with AVICTA Complete
Cotton to a popular variety without resistance (PHY 375B2RF),
also treated with AVICTA Complete Cotton. Additionally plots
planted to each variety as above and fumigated with Telone II (4
gal/A), were compared to non-fumigated plots. It was hoped that
the results from this study would give growers in eastern
Georgia better idea strategies to integrate nematode resistance
and nematicides into their cotton production practices.
RESULTS and DISCUSSION
1. The field trial at the Jeff Deen farm is pictured in photos above just
prior to harvest. Plots fumigated with Telone II are obvious; however it is
not possible to differentiate plots planted to PHY 367B2RF versus PHY
375B2RF.
2. From nematode samples collected after harvest (Figure 1) it is clear
that the populations of root-knot nematodes in the field far exceed the
economic threshold established for Georgia (100 juveniles/100cc soil).
Despite use of a resistant variety (PHY 367B2RF), high counts were
found in all treatments.
3. Plots originally to be treated with Vydate CLV following emergence
were used as a second set of AVICTA Complete Cotton treatments. This
proved fortuitous as areas planted were more affected by nematodes
than the first set.
ABSTRACT
Management of the plant-parasitic nematodes is of critical
importance throughout Georgia and annually costs producers
more than $100 million. The southern root-knot nematode
(Meloidogyne incognita) is especially important in Appling County
where sandy soils and long-term cotton production allow for
damaging populations of this organism to develop quickly. The
objective of this study was to determine appropriate management
strategies for management of M. incognita with the use of a
partially resistant variety (PHY 367B2RF), a seed treatment
nematicide (AVICTA Complete Cotton) and Telone II. The
population of M. incognita in the field used in this study was as
much as 6X the economic threshold level for the southern root-
knot nematode in Georgia. Little difference was noted between
damage to the PHY 367 versus PHY 375. Yield for resistant PHY
367 treated with AVICTA was 191 lb/A greater than where PHY
375 was planted. Fumigation with Telone II in conjunction with
either variety resulted in a numeric reduction in root-damage and
an increase in yield (413 lb/A).
D.S. Curry1and R.C.Kemerait2
1University of Georgia Coop. Ext., Baxley, GA 315191 and 2Dept. of Plant Pathology, University of Georgia, Tifton, GA,
31793.
Data reported in Figures 3 and 4 are based upon combined harvest of all plots of a given
treatment. Plots for the treatment PHY 367 + AVICTA + Telone II were not harvested due
to error. Seed-cotton yields for plots treated with Telone II were more than 300 lb/A
greater than were yields in plots that were not fumigated. However, based upon reported
gin turn-out, reported lint differences are much greater than anticipated. ALSO: Data for
the AVICTA-ONLY treatments does not include the second set of plots where damage
from nematodes was most severe.
MATERIALS and METHODS
1. A replicated field trial was established on the Jeff Deen farm in Appling
County, Georgia in 2011. This field has a history of losses to M. incognita.
2. The experimental design was a factorial randomized complete block with
3 replications. Treatments included combinations of PHY 367B2RF and
PHY375B2RF (seed treated with AVICTA Complete Cotton) with and
without Telone II (1,3-dichloropropene, 4 gal/A). Fumigation with occurred
weeks prior to planting. The cotton crop was planted on 7 Jun and
harvested on 15 Nov.
3. Vydate CLV, planned as a third treatment to compliment use of AVICTA
Complete Cotton, was not applied. Thus, there were two sets of plots
treated with AVICTA but not Vydate. Yield was not determined for the
second set of these pots.
4. Data collected included soil sampling to determine nematode
populations, end-of-season root-damage ratings, and yield (non-
replicated).
1048
0
200
400
600
800
1,000
1,200
1,400
1,600
PHY 375 + Telone +Avicta
PHY 367 + Avicta PHY 375 + Avicta
1,501
1,279
1,088
Yield/lbs Per acre
Figure 4. Lint Yield based upon gin turnouts reported by Satilla Cotton Gin
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
PHY 375 + Telone + Avicta PHY 367 + Avicta PHY 375 + Avicta
41%
36%
31%
% Lint
Figure 3. Gin Turn-out as determined by the Satilla Cotton Gin
A root system damaged by southern root-knot
nematodes (above, at right). In picture at right,
collecting soil samples after harvest to determine
end-of-season levels of plant parasitic nematodes.
0
10
20
30
40
Figure 2. Galls per gram of root at harvest
PHY367+AVICTA PHY375 + AVICTA
PHY367+AVICTA + Telone PHY375 + AVICTA+ Telone
PHY367 +AVICTA PHY375+AVICTA
B B B B
A A
0
200
400
600
800
Figure 1. M. incognita, juveniles/100cc soil at harvest
PHY367+AVICTA PHY375 + AVICTA
PHY367+AVICTA + Telone PHY375 + AVICTA+ Telone
PHY367 +AVICTA PHY375+AVICTA
NS SPECIAL NOTE: For Figures 1 and 2 two
sets of data are presented
for PHY 375 + AVICTA
and PHY 367 + AVICTA.
Originally the second set
was to be over-treated
with VYDATE CLV. As
this did not happen, the
plots were simply
duplicates of other
treatments. The data are
presented separately here
as results from this study
clearly document that
efficacy of seed-treatment
nematicides is closely tied
to the magnitude of
populations of parasitic
nematodes in a field.
Coincidentally, the second
set of seed treatments
was placed in severely
infected areas of the field.